[MachO] Add undefined atoms.

llvm-svn: 200649

2 files changed, 15 insertions, 2 deletions

diff --git a/lld/lib/ReaderWriter/MachO/File.h b/lld/lib/ReaderWriter/MachO/File.h
index 697c2e4d144..f67e3f4db80 100644
--- a/lld/lib/ReaderWriter/MachO/File.h
+++ b/lld/lib/ReaderWriter/MachO/File.h
@@ -37,6 +37,18 @@ public:
     addAtom(*atom);
   }
 
+  void addUndefinedAtom(StringRef name, bool copyRefs) {
+    if (copyRefs) {
+      // Make a copy of the atom's name and content that is owned by this file.
+      char *s = _allocator.Allocate<char>(name.size());
+      memcpy(s, name.data(), name.size());
+      name = StringRef(s, name.size());
+    }
+    SimpleUndefinedAtom *atom =
+        new (_allocator) SimpleUndefinedAtom(*this, name);
+    addAtom(*atom);
+  }
+
 private:
   llvm::BumpPtrAllocator _allocator;
 };
diff --git a/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp b/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp
index b91e3a81299..c84ca77367b 100644
--- a/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp
+++ b/lld/lib/ReaderWriter/MachO/MachONormalizedFileToAtoms.cpp
@@ -98,8 +98,9 @@ normalizedObjectToAtoms(const NormalizedFile &normalizedFile, StringRef path,
     processSymbol(normalizedFile, *file, sym, copyRefs);
   }
 
-  assert(normalizedFile.undefinedSymbols.empty() &&
-         "undefined symbols not supported yet!");
+  for (auto &sym : normalizedFile.undefinedSymbols) {
+    file->addUndefinedAtom(sym.name, copyRefs);
+  }
 
   return std::unique_ptr<File>(std::move(file));
 }